In many instances, it is desirable to provide a lock for securely locking a bicycle to a stationary object. It is also desirable to provide a lock which allows various parts and subassemblies of the bicycle to be locked together, such as, locking the rear wheel and the front wheel to the frame, as well as locking the frame to a stationary object. One method of providing such a means for locking a bicycle together is to use a cable or chain with a padlock. The storage of a cable or chain provides a problem to a bicycle rider. Locks having an extendible flexible shackle are known; and such locks are disclosed in U.S. Pat. No. 1,069,646 to Richter and U.S. Pat. No. 2,933,915 to Gossner. The prior art locks having a flexible shackle are not particularly adapted for use on a bicycle. These locks ordinarily lock the shackle at a selected length, but provide no means for retrieving the shackle into a housing once the lock is locked.